package com.lzq.lottery_system.service.mq;

import cn.hutool.core.date.DateUtil;
import com.lzq.lottery_system.common.exception.ServiceException;
import com.lzq.lottery_system.common.utils.JacksonUtil;
import com.lzq.lottery_system.common.utils.MailUtil;
import com.lzq.lottery_system.common.utils.SMSUtil;
import com.lzq.lottery_system.controller.param.DrawPrizeParam;
import com.lzq.lottery_system.dao.dataobject.ActivityPrizeDO;
import com.lzq.lottery_system.dao.dataobject.WinningRecordDO;
import com.lzq.lottery_system.dao.mapper.ActivityPrizeMapper;
import com.lzq.lottery_system.dao.mapper.WinningRecordMapper;
import com.lzq.lottery_system.service.DrawPrizeService;
import com.lzq.lottery_system.service.activitystatus.ActivityStatusManager;
import com.lzq.lottery_system.service.dto.ConvertActivityStatusDTO;
import com.lzq.lottery_system.service.enums.ActivityPrizeStatusEnum;
import com.lzq.lottery_system.service.enums.ActivityPrizeTiersEnum;
import com.lzq.lottery_system.service.enums.ActivityStatusEnum;
import com.lzq.lottery_system.service.enums.ActivityUserStatusEnum;
import jakarta.annotation.Resource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.amqp.rabbit.annotation.RabbitHandler;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import static com.lzq.lottery_system.common.config.DirectRabbitConfig.QUEUE_NAME;

@Component
@RabbitListener(queues = QUEUE_NAME)
public class MqReceiver {

    private static final Logger logger = LoggerFactory.getLogger(MqReceiver.class);

    @Autowired
    private DrawPrizeService drawPrizeService;
    @Autowired
    private ActivityStatusManager activityStatusManager;
    @Qualifier(value = "asyncServiceExecutor")
    @Autowired
    private ThreadPoolTaskExecutor threadPoolTaskExecutor;
    @Autowired
    private MailUtil mailUtil;
    @Autowired
    private SMSUtil smsUtil;
    @Autowired
    private ActivityPrizeMapper activityPrizeMapper;
    @Autowired
    private WinningRecordMapper winningRecordMapper;

    @RabbitHandler
    public void process(Map<String, String> message) {
        //成功接受到队列里的消息
        logger.info("Mq成功接收到消息, message:{}",
                JacksonUtil.writeValueAsString(message));
        String paramString = message.get("messageData");
        DrawPrizeParam param = JacksonUtil.readValue(paramString, DrawPrizeParam.class);
        //处理抽奖流程
        try {
            //校验抽奖请求是否有效
            if (!drawPrizeService.checkDrawPrizeParam(param)) {
                return;
            }
            //状态扭转处理
            statusConvert(param);
            //保存中奖者名单
            List<WinningRecordDO> winningRecordDOList = drawPrizeService.saveWinnerRecord(param);
            //通知中奖者(短信,邮箱)
            //抽奖之后的后续流程,异步处理
            syncExecute(winningRecordDOList);
        } catch (ServiceException e) {
            logger.error("处理MQ消息异常! {}:{}", e.getCode(), e.getMessage(), e);
            //如果异常,需要保持事务一致性(回滚)
            rollback(param);
            // 抛出异常: 消息重试
            throw e;
        }catch (Exception e) {
            logger.error("处理MQ消息异常! ", e);
            //如果异常,需要保持事务一致性(回滚)
            rollback(param);
            // 抛出异常
            throw e;
        }
    }

    /**
     * 处理抽奖流程异常的回滚:恢复处理请求之前的库表状态
     *
     * @param param
     */
    private void rollback(DrawPrizeParam param) {
        // 1、回滚状态：活动、奖品、人员
        // 状态是否需要回滚
        if (!statusNeedRollback(param)) {
            // 不需要：return
            return;
        }
        // 需要回滚: 回滚
        rollbackStatus(param);

        // 2、回滚中奖者名单
        // 是否需要回滚
        if (!winnerNeedRollback(param)) {
            // 不需要：return
            return;
        }
        // 需要: 回滚
        rollbackWinner(param);
    }

    /**
     * 回滚中奖记录: 删除奖品下的中奖者
     *
     * @param param
     */
    private void rollbackWinner(DrawPrizeParam param) {
        drawPrizeService.deleteRecords(param.getActivityId(), param.getPrizeId());
    }

    private boolean winnerNeedRollback(DrawPrizeParam param) {
        // 判断活动中的奖品是否存在中奖者
        int count = winningRecordMapper.countByAPId(param.getActivityId(), param.getPrizeId());
        return count > 0;
    }

    /**
     * 恢复相关状态
     *
     * @param param
     */
    private void rollbackStatus(DrawPrizeParam param) {
        // 涉及状态的恢复，使用 ActivityStatusManager
        ConvertActivityStatusDTO convertActivityStatusDTO = new ConvertActivityStatusDTO();
        convertActivityStatusDTO.setActivityId(param.getActivityId());
        convertActivityStatusDTO.setTargetActivityStatus(ActivityStatusEnum.RUNNING);
        convertActivityStatusDTO.setPrizeId(param.getPrizeId());
        convertActivityStatusDTO.setTargetPrizeStatus(ActivityPrizeStatusEnum.INIT);
        convertActivityStatusDTO.setUserIds(
                param.getWinnerList().stream()
                        .map(DrawPrizeParam.Winner::getUserId)
                        .collect(Collectors.toList())
        );
        convertActivityStatusDTO.setTargetUserStatus(ActivityUserStatusEnum.INIT);
        activityStatusManager.rollbackHandlerEvent(convertActivityStatusDTO);
    }

    private boolean statusNeedRollback(DrawPrizeParam param) {
        // 判断活动+奖品+人员表相关状态是否已经扭转（正常思路）
        // 扭转状态时，保证了事务一致性，要么都扭转了，要么都没扭转（不包含活动）：
        // 因此，只用判断人员/奖品是否扭转过，就能判断出状态是否全部扭转
        // 不能判断活动是否已经扭转
        // 结论：判断奖品状态是否扭转，就能判断出全部状态是否扭转
        ActivityPrizeDO activityPrizeDO =
                activityPrizeMapper.selectByAPId(param.getActivityId(), param.getPrizeId());
        // 已经扭转了，需要回滚
        return activityPrizeDO.getStatus()
                .equalsIgnoreCase(ActivityPrizeStatusEnum.COMPLETED.name());
    }

    /**
     * 并发处理抽奖后续流程
     *
     * @param winningRecordDOList
     */
    private void syncExecute(List<WinningRecordDO> winningRecordDOList) {
        //通过线程池 threadPoolTaskExecutor
        //扩展: 加入策略模式或其他设计模式
        //短信通知
        threadPoolTaskExecutor.execute(
                () -> sendMessage(winningRecordDOList));
        //邮件通知
        threadPoolTaskExecutor.execute(
                () -> sendMail(winningRecordDOList));
    }

    /**
     * 发邮件
     *
     * @param winningRecordDOList
     */
    private void sendMail(List<WinningRecordDO> winningRecordDOList) {
        if (CollectionUtils.isEmpty(winningRecordDOList)) {
            logger.info("中奖列表为空，不用发邮件！");
            return;
        }
        for (WinningRecordDO winningRecordDO : winningRecordDOList) {
            // Hi,胡一博。恭喜你在抽奖活动活动中获得二等奖:吹风机。获奖奖时间为18:18:44,请尽快领取您的奖励
            String context = "Hi，" + winningRecordDO.getWinnerName() + "。恭喜你在"
                    + winningRecordDO.getActivityName() + "活动中获得"
                    + ActivityPrizeTiersEnum.forName(winningRecordDO.getPrizeTier()).getMessage()
                    + "：" + winningRecordDO.getPrizeName() + "。获奖时间为"
                    + DateUtil.formatTime(winningRecordDO.getWinningTime()) + "，请尽快领取您的奖励！";
            mailUtil.sendSampleMail(winningRecordDO.getWinnerEmail(),
                    "中奖通知", context);
        }
    }

    /**
     * 发短信
     *
     * @param winningRecordDOList
     */
    private void sendMessage(List<WinningRecordDO> winningRecordDOList) {
        if (CollectionUtils.isEmpty(winningRecordDOList)) {
            logger.info("中奖列表为空，不用发短信！");
            return;
        }
        for (WinningRecordDO winningRecordDO : winningRecordDOList) {
            Map<String, String> map = new HashMap<>();
            map.put("name", winningRecordDO.getWinnerName());
            map.put("activity", winningRecordDO.getActivityName());
            map.put("kind", ActivityPrizeTiersEnum.forName(winningRecordDO.getPrizeTier()).getMessage());
            map.put("product", winningRecordDO.getPrizeName());
            map.put("time", DateUtil.formatTime(winningRecordDO.getWinningTime()));
            smsUtil.sendMessage("SMS_474780549",
                    winningRecordDO.getWinnerPhoneNumber().getValue(),
                    JacksonUtil.writeValueAsString(map));
        }
    }

    /**
     * 状态扭转
     *
     * @param param
     */

    private void statusConvert(DrawPrizeParam param) {
        ConvertActivityStatusDTO convertActivityStatusDTO = new ConvertActivityStatusDTO();
        convertActivityStatusDTO.setActivityId(param.getActivityId());
        convertActivityStatusDTO.setTargetActivityStatus(ActivityStatusEnum.COMPLETED);
        convertActivityStatusDTO.setPrizeId(param.getPrizeId());
        convertActivityStatusDTO.setTargetPrizeStatus(ActivityPrizeStatusEnum.COMPLETED);
        convertActivityStatusDTO.setUserIds(
                param.getWinnerList().stream()
                        .map(DrawPrizeParam.Winner::getUserId)
                        .collect(Collectors.toList())
        );
        convertActivityStatusDTO.setTargetUserStatus(ActivityUserStatusEnum.COMPLETED);
        activityStatusManager.handleEvent(convertActivityStatusDTO);
    }
//    private void statusConvert(DrawPrizeParam param) {

        //问题:
        //1.活动状态扭转有依赖性
        //2.状态扭转可能会扩展,当前写法扩展性差,维护性差
        //解决方案: 设计模式(责任链设计模式,策略模式)

        //活动: RUNNING-->COMPLETED 全部奖品抽完之后才改变状态
        //奖品: INIT-->COMPLETED
        //人员列表: INIT-->COMPLETED

        //1.扭转奖品状态
        //查询活动关联的奖品信息
        //条件判断是否符合扭转奖品状态: 判断当前状态是否, 不是COMPLETED, 如果不是, 要扭转
        //才去扭转

        //2.扭转人员状态
        //查询活动关联的人员信息
        //条件判断是否符合扭转人员状态: 判断当前状态是否, 不是COMPLETED, 如果不是, 要扭转
        //才去扭转

        //3.扭转活动状态
        //查询活动信息
        //条件判断是否符合扭转活动状态: 判断当前状态是否, 不是COMPLETED, 如果不是且全部奖品抽完之后, 要扭转
        //才去扭转

        //更新活动完整信息缓存

//    }
}
